Machine head for spot welding for crimping

Abstract

The force (F) is derived from one or several electromagnetic forces each one of which is developed by the effect of a current (I s , I B ) that circulates through a conductor (8) buried within a magnetic field.

I claim: 
     
       1. A head for a spot-welding machine or for a crimping machine, said head comprising an electrode (3) for supplying a welding or crimping current (I s ) to a part (6a) which is welded onto another part (6b), or which is crimped, said electrode exerting a force (F) on said part (6a) during a welding or crimping operation, an electromagnet (10), and means for developing said force (F) responsive to at least one magnetic force, said magnetic forces being developed by the effect of a current (I s , I B ) that circulates through a conductor flux lines of a magnetic field which is generated by said electromagnet (10). 
     
     
       2. A head according to claim 1, wherein the current that circulates through said conductor (8) is the welding or crimping current (I s ). 
     
     
       3. A head according to claim 1, wherein the current that circulates through said conductor (8) is a current delivered by a source of current (9, 9') governed by a governing and control unit. 
     
     
       4. A head according to any one of the preceding claims 1-3, wherein said conductor (8) is mounted to move within a plane that cuts the flux lines of said magnetic field. 
     
     
       5. A head according to claim 4, wherein said conductor (8) is mounted to pivot within a plane that cuts the flux lines of said magnetic field. 
     
     
       6. A head according to claim 4, wherein electrode (3) is one piece with said conductor (8), said one piece being movable. 
     
     
       7. A head according to claim 4, wherein said movable electrode (3) is fixed at a free end of said conductor (8). 
     
     
       8. A head according to claim 4, wherein said electrode (3) is affixed to a free end of an arm (4) coupled to pivot at the same time as said conductor (8) pivots. 
     
     
       9. A head according to claim 8, wherein said arm (4) is electrically insulated from said conductor (8) and opposite ends of said conductor (8) respectively are connected to the terminals of a source (9) of current, said welding current running through said arm (4).